Answer:
downward
Step-by-step explanation:
The motion of the student is a uniformly accelerated motion, so we can use the suvat equation

where, taking downward as positive direction, we have
s = 15.6 m is the vertical displacement
u = 0 is the initial velocity (we assume the student starts from rest)
t = 1.80 s is the time of the fall
a is the acceleration of the student
By re-arranging the equation and solving for a, we can find the acceleration of the student:

And since the sign is positive, the direction of the acceleration is downward.